How to move assets with a button click in BGE
Possible example: This will move the ball in one direction, if you press the button.
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To detect the click on your button add a mouse over sensor and a left button sensor to your button. Combine them with the default AND controller and use a message actuator to send a message e.g. "moving" to your ball.
Make sure that one of the Sensors has true-level-triggering enabled, so your ball keeps moving while you keep pressing.



Catch that message to your ball with a message sensor (set right subject) and connect it with the motion you want.